In modern hybrid and electric motor vehicles lithium ion batteries are frequently used as rechargeable energy stores. A battery optimized with regard to service life and maximum energy storage amount requires a corresponding high-performance temperature control device for the individual battery cells, which is capable of preventing in particular heating of the battery beyond a maximum operating temperature.
The heating and cooling power made available by the temperature control device should be distributed as evenly as possible to the individual battery cells of the lithium ion battery precisely during the tempering of lithium ion batteries. If the tempering is carried out via a heating or cooling plate to which the battery cells are thermally connected via surface contact, this creates the need for an almost completely homogeneous plate temperature. If the plate is directly or indirectly tempered with the aid of a fluid acting as heating or cooling agent, optionally in combination with Peltier elements, then the inlet temperature of the fluid in the temperature control device is different from the outlet temperature, since the fluid has absorbed heat in the case of cooling and has released heat in the case of a heating. From this it follows, however, with homogeneous heat transfer coefficients from fluid to battery, that the battery cells to be tempered do not undergo a spatially uniform heat supply or dissipation and are thus not homogeneously tempered.
Against this background, cooling systems are known from the prior art that allow heat exchange between the battery and the cooling plates via two cooling plates configured as half shells that form a cooling agent channel for a cooling agent when attached to each other, wherein the enthalpy of evaporation of the battery required for evaporation of the fluid cooling agent is extracted in the form of heat. If a merely single-phase cooling agent is used, that is, one that is available only in liquid form, the heat exchange can then be supported by thermoelectric elements, for instance in the form of Peltier elements, which are mounted at defined points between the battery to be cooled and the cooling plates.
One possibility for counteracting the undesirable effect of spatially inhomogeneous tempering of the battery cells is to achieve an on average homogeneous distribution of the fluid temperature via adjacent fluid channels with alternating flow direction between two ends of a plate. A combined intake and exhaust manifold is provided on the temperature control device in such a scenario. The fluid is introduced into the manifold via a fluid inlet and is there distributed to the different adjacent fluid channels with the aid of suitable direction-defining structures, through which the thermal interaction of the fluid with the battery cells can take place. After flowing through the fluid channels, the fluid flows back again into the intake and exhaust manifold and is channeled out of it through a joint fluid outlet. DE 10 2012 211 259 A1, which is known from the prior art, discloses an intake and exhaust manifold that operates according to this principle.
However, such an application necessarily presupposes a design of the intake and exhaust manifold with three-dimensional flow structures, resulting in markedly higher manufacturing costs for the production of the intake and exhaust manifold.
It is therefore an object of the invention to create a combined intake and exhaust manifold that has a simply designed configuration and in which the above-mentioned disadvantages are no longer present.